Continuous mining apparatus of the reversible longwall type



April 5, 1955 C. F. BALL CONTINUOUS MINING APPARATUS OF THE REVERSIBLE LONGWALL TYPE Filed April 9, 1949 17 Sheets-Sheet l C. F. BALL April 5, 1955 CONTINUOUS MINING APPARATUS OF THE REVERSIBLE LONGWALL TYPE Filed April 9. 1949 17 Sheets-Sheet 2 C. F. BALL April 5, 1955 CONTINUOUS MINING APPARATUS OF THE REVERSIBLE LONGWALL TYPE Filed April 9, 1949 17 Sheets-Sheet 3 4 n w Q SN? @Ww W l y no b `n m\\ QQ. www. `0 M o o T oo n n 1 mvmhbm f @@J.. ,uw o ww Ww o o o w f m, o O w ;:Smwel/o \5\ l, ba Si ,fr C BS m y w Jf/ www Si ,@m. m3 um N mm 90nd W coNTINUoUs MINING APPARATUS oF THE REVERSIBLE LoNGwALL TYPE- Filed April 9, 1949 C. F. BALL April 5, 1955 17 'Sheets-Sheet 4 www Bbw

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United States Patent O CONTINUOUS MINING APPARATUS OF THE REVERSIBLE LONGWALL TYPE Application April 9, 1949, Serial No. 86,516

21 Claims. (Cl. 26228) This invention relates to a mining apparatus and more particularly to a continuous mining apparatus for removing minerals such as coal from a solid mine vein in a substantially uninterrupted manner without the use of explosives, and for conveying the dislodged mineral or coal as it is removed from the mine vein to a convenient point of delivery.

Mining apparatus of the character of the present invention is designed mechanically to remove completely, by a unitary and self-contained machine, minerals such as coal from a solid mine vein or coal seam in a relatively continuous and uninterrupted manner, thereby eliminating the conventional separate steps of cutting, drilling, blasting and loading the mineral or coal by means of separate pieces of equipment. The mineral or coal as it is dislodged from the mine vein or coal seam is suitably collected, properly broken to size, and conveyed to a convenient point of delivery remote from the working face so that manual loading of the mineral or coal is substantially avoided. By reason of the extreme compactness, both vertically and laterally, of the apparatus of the present invention, the same is particularly adapted to use in the relatively restricted spaces resulting from close roof propping or timberng common to longwall faces encountered in the longwall system of mining, and since such an apparatus must operate in opposite directions along the longwall face in accordance with such system, the apparatus of the present invention is made readily reversible without the necessity of complete turning around of the apparatus. The apparatus of the present invention, due to its novel features of construction, is ideally suitable for the complete mechanical mining and loading of minerals such as coal from a longwall face, from thin coal seams or veins, and, due to its lateral compactness, may be conveniently moved through the narrow and relatively restricted passageways commonly encountered in mining in accordance with the longwall system. Moreover, the mining apparatus of the present invention further is capable of performing all essential work in the formation of roadways opening laterally of the longwall face, and in the formation of recesses or open spaces in the coal seam or vein of sufficient area to permit turning of the vein attacking and disintegrating mechanism at the ends of a longwall face, thereby enabling ready reversal of the apparatus to effect removal of the coal or other mineral from the working face in either direction along the longwall face without the need of completely turning the apparatus around. Further, the apparatus of the present invention not only simplies timbering but also, due to its novel features of construction, is capable of completely removing in a substantially uninterrupted manner the mineral or coal from the longwall face of a solid mine vein or coal seam without the use of explosives, thus facilitating and expediting removal of the mineral or coal and making the working conditions safer and less detrimental to health.

The invention, from a broad aspect, resides in improvements in a continuous mining apparatus of a compact construction especially adapted for use in underground coal mines having low head room, and including vein disintegrating mechanism for removing relatively wide vertical segments of the Working face, for breaking up oversize chunks of the dislodged coal, and for conveying the dislodged and broken up coal away from the working face to a convenient point of delivery, all in a novel manner. The invention, from a more specific aspect, resides in improvements in a continuous mining apparatus which 2,705,625 Patented Apr. 5, 1955 ICC is extremely laterally compact and adapted to remove coal from a longwall coal face and to move parallel to the face in the restricted space provided. between the coal face and the face conveyor, and may comprise a mobile base, such as a crawler base, carrying a swivelled frame swingable horizontally about an upright axis located centrally of the base, with respect to the base, and carrying a frame structure which projects in advance of the base and which is swingable in vertical planes relative to the swivelled frame and swingable horizontally with the swivelled frame with respect to the base. Power devices may be provided for turning the swivelled frame and for vertically swinging the frame structure about their respective pivots. The swingable frame structure is extensible to vary its effective length and has power devices for extending and retracting the same, and supports at its extendable outer portion the vein or coal seam attacking and disintegrating mechanism. The swivelled frame is swingable horizontally relative to the base to locate the vein-attacking and disintegrating mechanism in different lateral positions angularly with respect to the swivel axis and the vein-attacking and disintegrating mechanism is disposable with respect to the working face in a position to be sumped into the coal at the oor level by extending the frame structure by its power devices, and when the outer portion of the attacking and disintegrating mechanism has been sumped into the coal, the frame structure may be swung upwardly by its power devices at a relatively high speed and with a powerful upward thrust to cause the attacking and disintegrating mechanism to effect dislodgment, with a ripping or tearing action, of a veritcal segment of the working face of the coal between the sumped position of the attacking and disintegrating mechanism and its raised position at the roof level. The disintegrated coal or mineral is moved rearwardly along the top of the attacking and disintegrating mechanism to discharge into a breaker and hopper device wherein any oversize chunks of coal or other mineral are reduced to proper size and conducted downwardly to a front conveyor carried by the rearward portion of the frame structure beneath the rearward portion of the attacking and disintegrating mechanism, and this conveyor may in turn discharge onto a main discharge conveyor overlying the base and arranged crosswise of the base. When the attacking and disintegrating mechanism reaches the end of its upward stroke at the roof level, the frame structure may be retracted by its power devices to withdraw the attacking and disintegrating mechanism from the working face, and the attacking and disintegrating mechanism may then be lowered and positioned laterally, and may again be sumped into the coal and swung upwardly to remove an adjacent vertical segment of the working face. The base may then be advanced along the longwall face to a new operating position and under certain conditions the swivelled frame may be turned on its swivel relative to the base to locate the disintegrating mechanism at different angles of attack with respect to the face of the coal, and the sumping, swinging and withdrawal operations above described may be repeated in any position of adjustment of the disintegrating mechanism to effect disintegration of vertical segments of the working face. By angularly positioning the disintegrating mechanism with respect to the base successive segments of coal may be dislodged from the coal seam to provide a widened space at either end of the longwall face of suiiicient area to permit reversal of the attacking and disintegrating mechanism as will later be explained. The disintegrated coal or other mineral which is discharged onto the transverse conveyor by the front conveyor may be conveyed to a suitable point of delivery laterally of the base such as on a face conveyor arranged parallel with the face at the prop side of the apparatus between the latter and the roof props. Any loose coal or other mineral which falls from the attacking and disintegrating mechanism or directly from the working face onto the mine oor during the dislodging operation, may be picked up or gathered by a front shovel or scraper and a gathering conveyor carried at the front end of the base and this gathering conveyor is arranged on the base to discharge onto the transverse conveyor. The apparatus is designed to 'operate in either of opposite directions along the longwall face and the swivelled frame may be swung on its swivelled mounting to position the attacking and disintegrating mechanism to operate at either end of the base which is reversible, and a second transverse conveyor on the base is arranged to receive the disintegrated coal discharged from the front conveyor in the reversed position of the disintegrating mechanism. Also, a second gathering conveyor may be arranged at the opposite end of the base and the shovel or scraper may be transposed to the opposite end of the base so that any loose coal on the mine oor may be dlrected toward such second gathering conveyor during reverse movement of the apparatus. The transverse conveyors are symmetrically arranged on the base at the opposite ends of the latter and at opposite sides of the frame swivel so that they may receive the disintegrated mineral or coal discharged from the front conveyor in either of the reversed positions of the attacking and disintegrating mechanism and are so arranged and constructed that they may be extended in an endwise direction laterally from one side of the base irrespective of direction in which the apparatus is operating.

An object of the present invention is to provide an improved mining apparatus. Another object is to provide an improved continuous mining apparatus capable of operating in either of opposite directions along a longwall face of an underground coal mine. Yet another object is to provide an improved continuous mining apparatus which is extremely compact, both vertically and laterally, whereby the apparatus may readily move through the restricted passageways and low head room encountered in the mining of coal in accordance with the longwall system. A further object is to provide an improved mining apparatus whereby the coal of the working face of a coal seam may be dislodged from the solid without the use of explosives, and the dislodged coal may be conveyed to a convenient loading point without need of manually handling the dislodged coal. A still further object is to provide an improved continuous mining and loading apparatus which is extremely compact both vertically and laterally and which is also extremely flexible in operation and sensitive to control. Still another object is to provide an improved continuous mining apparatus having veinattacking and disintegrating mechanism which is disposable in reversed positions with respect to the base of the apparatus whereby coal may be dislodged from a coal face during movement of the apparatus in either of opposite directions along the face. Another object is to provide an improved continuous miner especially designed for use in accordance with the longwall system of mining and which embodies improved coal attacking and disintegrating mechanism which may be reversely positioned with respect to the base of the apparatus whereby the coal may be dislodged from the face of the mine vein during either direction of movement in the apparatus, and embodying means whereby the apparatus may be readily reversed. A further object is to provide an improved conveying means for a continuous miner of the reversible longwall type whereby the coal dislodged from the coal seam may be loaded at a convenient point remote from the coal face irrespective of the direction in which the apparatus is operating. Still another object is to provide an improved continuous mining apparatus comprising a mobile base having a swivelled frame mounted thereon to swing horizontally with respect thereto and carrying an extensible frame structure which is swingable in vertical planes and on the outer portion of which coal-detaching, faccattacking and disintegrating mechanism is carried whereby when the frame structure is extended and retracted, the attacking and disintegrating mechanism may be sumped into the coal seam or retracted from the coal face, and having embodied therein improved means for swinging the frame structure in vertical planes to effect movement of the disintegrating mechanism vertically in an arcuate path from its sumped position near the oor level to its raised position at the roof level. Another object is to provide an improved continuous mining apparatus of the above character wherein the swivelled frame is swingable to locate the coal-attacking and disintegrating mechanism at either end of the base to enable operation of the apparatus in either direction along a longwall coal face. Still a further object is to provide an improved mining apparatus having a mobile base adapted to move in either direction along a longwall coal face and carrying a gathering or cleanup conveyor at both of its opposite ends whereby any loose coal on the mine floor may be gathered and discharged on a transverse conveyor during either direction of movement of the base. Another object is to provide an improved reversible cont1nuous miner of the longwall type adapted to operate in either of opposite directions along a longwall coal face and embodying reversible vein-attacking and disintegrating mechanism and conveying means on the base onto which the disintegrated coal may be discharged during either direction of operation of the apparatus. A further object is to provide an improved reversible continuous mining apparatus adapted to operate in either of opposite directions along a longwall coal face and adapted continuously to load the disintegrated coal onto a face conveyor arranged parallel with the coal face during either direction of operation of the apparatus. Still another object is to provide an improved reversible continuous mining apparatus of the longwall type embodying reversible coal attacking and disintegrating mechanism which is adapted to dislodge coal successively in relatively wide vertical segments at either end of the longwall face to provide suicient turning area for the attacking and disintegrating mechanism whereby the apparatus rnay be readily reversed. Another object is to provide an improved mining and loading apparatus having a novel combination and arrangement of parts. These and other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawings there is shown for purposes of illustration one form which the invention may assume in practice.

In these drawings:

Fig. 1 is a plan view of a continuous mining apparatus constructed in accordance with the preferred illustrative embodiment of the invention.

Fig. 2 is a side elevational view of the mining apparatus shown in Fig. 1, with the vein-attacking and disintegrating mechanism in its lowered, retracted position.

Fig. 3 is an enlarged central longitudinal vertical sectional view taken substantially on line 3 3 of Fig. l, illustrating details of the forward portion of the mining apparatus.

Fig. 4 is an enlarged central longitudinal vertical sectional view taken substantially on line 4 4 of Fig. 1, illustrating details of the rearward portion of the mining apparatus.

Fig. 5 is a fragmentary side elevational view of the forward portion of the mining apparatus, showing the vein attacking and disintegrating mechanism in its forward extended position at the oor level.

Fig. 6 is an enlarged horizontal sectional view taken substantially on the planes of line 6 6 of Fig. 2.

Fig. 7 is an enlarged horizontal sectional view taken substantially on line 7 7 of Fig. 2, illustrating details of one of the crawler tread structures.

Fig. 8 is a vertical sectional view taken substantially on line 8 8 of Fig. 7.

Fig. 9 is an enlarged cross-sectional view taken substantially on line 9 9 of Fig. 1.

Fig. 10 is a detail horizontal sectional view taken on line 1.0 10 of Fig. 4.

Fig. 11 is an enlarged detail sectional view taken on the planes of line 11 11 of Fig. 3, illustrating details of the vein-attacking and disintegrating mechanism.

Fig. l2 is a front end view of the mechanism shown in Fig. l, with the disintegrating chains omitted to facilitate illustration.

Fig. 13 is a side view of the mechanism shown in Fig. 12, showing a rotary side disintegrator.

Fig. 14 is a detail sectional view taken on the planes of line 1414 of Fig. 13, illustrating details of one o the rotary side disintegrators.

Fig. 15 is a detail sectional view taken on the plane of line 15-15 of Fig. 4, with the chains omitted.

Fig. 16 is a horizontal section taken on line 16-16 of Fig. 18.

Fig. 17 isla detail longitudinal vertical sectional view taken substantially on line 17 17 of Fig. 15, illustrating a portion of the drive for the vein-attacking and disintegrating mechanism.

Fig. 18 is an enlarged detail longitudinal vertical sectional view taken on line 18-18 of Fig. 6.

Fig. 19 is a plan view, with parts shown in horizontal section, illustrating a portion of the drive for the transverse discharge conveyors.

Fig. 2,0 is an enlarged detail vertical sectional view taken substantially on the planes of line --20 of Fig. 1.

Fig. 21 is a detail horizontal sectional view taken on line 2121 of Fig. 20.

Fig. 22 is a sectional view taken substantially 0n line 22-22 of Fig. 4, showing the front conveyor.

Fig. 23 is a detail vertical sectional view taken on line 23-23 of Fig. 22, illustrating the details of the front conveyor drive.

Fig. 24 is a plan view taken on line 24--24 of Fig. 2, showing the detachable front shovel or scraper.

Fig. is an enlarged plan view taken on line 25-25 of Fig. 3, illustrating details of one of the gathering or pickup conveyors.

Fig. 26 is a central longitudinal vertical sectional view taken on line 26-26 of Fig. 25.

Fig. 27 is an enlarged detail vertical sectional view taken on line 27-27 of Fig. 25

Fig. 28 is an enlarged fragmentary plan view of the gathering conveyor shown in Fig. 25.

Figs. 29 and 30 are detail vertical sectional views taken respectively on lines 29-29 and 30-30 of Fig. 28.

Fig. 3l is a detail cross-sectional view taken on line 31--31 of Fig. 28.

Fig. 32 is a perspective view of a pair of adjacent conveyor links of the gathering conveyor shown in Fig. 28.

Fig. 33 is a diagrammatic view showing the hydraulic fluid system and associated control valve means of the apparatus.

Fig. 34 is a diagrammatic view in plan showing the.

mining apparatus operating in accordance with the longwall system of mining, with the apparatus operating to dislodge a series of vertical segments of coal from the coal face to provide a widened space to permit reversal of the vein-attacking and disintegrating mechanism.

Fig. is a diagrammatic View in plan, similar to Fig. 34, illustrating a different manner of operating the mining apparatus in accordance with the longwall system.

Figs. 36 to 40 inclusive are diagrammatic views in plan illustrating the manner of reversing the apparatus at the end of a longwall face.

Fig. 4l is a diagrammatic side view of the apparatus operating in a mine, showing the vein-attacking and disintegrating mechanism in sumping, sumped and raised positions as indicated in full and dotted lines.

The improved continuous mining apparatus, as shown in the drawings, constitutes an improvement over that disclosed in a copending application of common ownership of one Harold F. Silver, Ser. No. 11,688, tiled February 27, 1948, and generally comprises a mobile base l, herein a tractor or crawler base, adapted to travel over the oor of a mine, and carrying centrally thereof a vertical swivel 2, on which a horizontal supporting frame 3 is mounted to swing horizontally with respect to the base, and which, in turn, has an extensible frame structure or head frame 4 pivotally mounted thereon at 5 to swing in vertical planes with respect thereto and to swing in horizontal planes therewith relative to the base. The extensible frame structure 4 extends forwardly in advance of the base and carries, at its outer portion, vein or coal seam-attacking and disintegrating mechanism or dislodging head generally designated 6, for detaching and disintegrating minerals such as coal in relatively wide vertical segments from a solid mine vein or coal seam. The detached and disintegrated mineral or coal is moved by the attacking and disintegrating mechanism 6 rearwardly along the top thereof and is discharged into a breaker and hopper device generally designated 7, in which any oversize chunks of mineral or coal are reduced to proper size and through which broken and disintegrated material is conducted to a front conveyor 8, herein carried by the rearward portion of the extensible frame structure 4 and underlying the rearward portion of the attacking and disintegrating mechanism 6. The conveyor 8 discharges on an endwise adjustable, transverse discharge conveyor or conveyor portion 9 mounted on the top of the base beneath the swivelled frame 3. The attacking and disintegrating mechanism discharges onto the front conveyor 8 in the different extended positions of the frame structure 4 and the front conveyor 8 discharges onto the transverse conveyor 9 in the different angular positions of the swivelled frame assumed during the operation of the attacking and disintegrating mechanism at one end of the base. The base is symmetrical end to end and the vein-attacking and disintegrating mechanism may be reversed with respect to the base simply by swinging the swivelled frame through to enable reverse operation of the apparatus, and a second endwise adjustable transverse conveyor or conveyor portion 10 is arranged on the base at the opposite side of the swivel 2 from the conveyor 9, in a position to receive the disintegrated mineral from the front conveyor 8 when the attacking and disintegrating mechanism is reversed with respect to the base. Arranged symmetrically at opposite ends of the bases are gathering or cleanup conveyors 11 and 12 mounted to swing in vertical planes and a transposable shovel or scraper 13 is attachable to either end of the base for directing loose material from the mine floor onto one of the pickup conveyors irrespective to the direction in which the apparatus is operating. A motor 14, preferably an electric motor, carried by the swivelled frame 3 serves to drive the veinattacking and disintegrating mechanism 6 and the auxiliary front conveyor 8; a motor 15, preferably a hydraulic motor, drives the cross conveyors 9 and 10; motors 16, 16, preferably hydraulic motors, drive the crawler treads 17 of the base; and motors 18, 18, preferably hydraulic motors, drive the gathering or cleanup conveyors 11 and 12. A motor 19, preferably a hydraulic motor, serves to swing the swivelled frame 3 on its swivelled mounting relative to the base. The crawler treads 17 of the base serve to tram the apparatus about the mine and to steer the apparatus by suitable control of the motors 16, 16. Extensible hydraulic jacks 20, 20 serve to extend and retract the swingable frame structure 4 and extensible hydraulic jacks 21, 21 serve to swing the frame structure in vertical planes.. Extensible hydraulic jacks 22, 22 and 23, 23 serve to raise the cleanup conveyor and scraper. Extensible hydraulic jacks 24, 24 serve to adjust the transverse conveyors 9 and 10. The motor 14 also drives pumping means 25 and 26 which supply liquid under pressure to the hydraulic devices above referred to. Arranged centrally of the vertical swivel 2 is a hydraulic roof jack 27 for holding the base steady and for supporting the roof above the apparatus during the coal dislodging operation.

The tractor or crawler base 1 comprises a horizontal frame 2S having an integral vertical tubular column or post 29 of sturdy construction arranged centrally thereof (Figs. 4 and 6), and secured at its sides to tread frames 30, 30 about which the endless crawler treads 17 are guided for circulation. Chain drive sprockets 31 are journaled on bearings supported by transverse shafts 32, and these shafts are secured at their ends within vertical side plates 33 of the tread frames 30 at one end of the latter as shown in Fig. 7. At the opposite ends of the tread frames are chain idler sprockets 34 keyed to the opposite end portions of transverse shafts 35 which are journaled in bearings supported by adjustable brackets 36. The brackets 36 are guided in longitudinal guideways 37 within the tread frames 30 and adjustable longitudinally by adjusting screws 38 threaded within the brackets, to vary the tension of the tread chains 17. The chain sprockets 31 engage and drive the tread chains 17 and in turn are driven by chain sprockets 39 secured thereto and engaged by endless drive chains 40 which are driven by chain sprockets 41. The hydraulic motors 16 are of the conventional reversible type and are arranged within the tread frames 30 as shown in Figs. 7 and 8, and have their power shafts connected through universal joints 42 to telescopic shafts 43 which are in turn connected by universal joints 44 to longitudinal shafts 45, the latter suitably journaled within bearings supported by brackets 46 secured to a gear case 47. Fixed to the shafts 45 are beveled pinions 48 which mesh with and drive beveled gears 49* lixed to transverse shafts 50. The shafts 50 are likewise suitably journaled within bearings supported by the gear case. Fixed to and driven by the shafts 50 are spur pinions 51 meshing with spur gears 52 fixed to shafts 53 herein arranged parallel with the shafts 50 and likewise suitably jour'- naled within bearings supported by the sides of the gear case. Fixed to the shafts 53 are spur pinions 54 meshing with spur gears 55 fixed to parallel shafts 56 likewise suitably journaled within bearings supported within the gear case 47. Spur pinions 57 fixed to each of the shafts 56 at opposite sides of the gear 55 mesh with and drive spur gears 58 fixed to a parallel shaft 59. The shafts 59 likewise are suitably journaled in bearings supported by the gear case. Meshing with and driven by the 

